/**
 * Copyright (C) 2015 Fernando Cejas Open Source Project
 * <p/>
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.fernandocejas.android10.sample.data.executor;


import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * Decorated {@link java.util.concurrent.ThreadPoolExecutor}
 */
public class JobExecutor implements ThreadExecutor {

	private static final int INITIAL_POOL_SIZE = 3;
	private static final int MAX_POOL_SIZE = 5;

	// Sets the amount of time an idle thread waits before terminating
	private static final int KEEP_ALIVE_TIME = 10;

	// Sets the Time Unit to seconds
	private static final TimeUnit KEEP_ALIVE_TIME_UNIT = TimeUnit.SECONDS;

	private final BlockingQueue<Runnable> workQueue;

	private final ThreadPoolExecutor threadPoolExecutor;

	private final ThreadFactory threadFactory;

	public JobExecutor() {
		this.workQueue = new LinkedBlockingQueue<>();
		this.threadFactory = new JobThreadFactory();
		this.threadPoolExecutor = new ThreadPoolExecutor(INITIAL_POOL_SIZE, MAX_POOL_SIZE,
				KEEP_ALIVE_TIME, KEEP_ALIVE_TIME_UNIT, this.workQueue, this.threadFactory);
	}

	@Override
	public void execute(Runnable runnable) {
		if (runnable == null) {
			throw new IllegalArgumentException("Runnable to execute cannot be null");
		}
		this.threadPoolExecutor.execute(runnable);
	}

	private static class JobThreadFactory implements ThreadFactory {
		private static final String THREAD_NAME = "android_";
		private int counter = 0;

		@Override
		public Thread newThread(Runnable runnable) {
			return new Thread(runnable, THREAD_NAME + counter);
		}
	}
}